This review is 100% garbage. You evaluated it AFTER you opened it up and you didn't even test it BEFORE you opened it up. You clearly broke connectors doing it, and then now users watching this will NEVER know if they have QC issues or your just an idiot. Vote this channel for worlds worst channel ever
Based on your review I bought one of these and set it up in my shop so can listen to music, etc. from my tablet. I hooked it to 2- 30w speakers 20' apart across the room and couldn't be happier! Clean rich sound and no distortion that I could perceive and more volume than I will ever use. As a bonus, I discovered that it turns itself off after a period of nonuse! Thanks for this review! It has made the time I spend in my shop more enjoyable. Regards
It's not like he abused it taking it apart... and it essentially was only 12 easy to access screws anyway... highly doubt it was anything he did. Even if it were something he did, it would have only happened if the build quality were low.
You are right about the single chip doing everything, it's a quite powerful microcontroller (32 bit and up to 160MHz operation), with built in radio receiver/transmitter for bluetooth. Manufactured by ZhuHai JieLi Technology Co.,ltd. Often they can do bluetooth, read sd cards and playback of mp3, depending on the programming and the particular IC version. A lot of them also have the dreaded 'The bluetooh device is successfully connected' voice that plays at full volume and in a dodgy Chinese accent. They are found in the mini mp3 players and generic bluetooth speakers.
At 3:54, when you first took it apart, you can clearly see the LGR connector is fully seated on the PCB. At 18:13 it's plain to see the connector is jacked up off the PCB by a good 3mm. This is not a build quality issue, had you not taken it apart it would be working perfectly. I deal with these connectors regularly and they are perfectly suitable for this purpose. They are not flawed when it comes to initial assembly, build quality, or careful servicing. They are, however, not foolproof when it comes to servicing. Some attention to detail is required.
M is the muting pin. The front board is the preamp, and the back board is the power amp. The signal on the M pin shuts down the power amp to prevent pops and clicks at power on/off and when changing sources or modes. (well, it's supposed to anyway...)
so the main amplifier is at full volume all the time and you only adjust the volume of the preamplifier (board/chip) and that signal is sent through LGR connector to the amplifier.
@@orange11squares Yes, that is pretty much how all amps work. When you set your vol. control to max, you are essentially removing all resistance between the input signal and the amp. Full input signal to amp = max volume.
ALWAYS test before disassembly. That is, if you want an ACCURATE review of a consumer's experience with product, as shipped. Once you dig into something, you taint the review. BTW: That is 50 Watts Peak Power with ampl amounts of distortion.
Sam Houston Assuming a very generous 90% efficiency, that fingernail-size heatsink is expected to dissipate 10W? Um, no... Great idea, horrible execution. If disassembly/reassembly as shown breaks it, no thanks.
@@artysanmobile Class D amplifiers have very low power dissipation. The output driver is either hard on or hard off. No analog modulation occurs, it is just feeding a very high frequency square wave to the speaker with pulse width modulation.
Allan Gibson I know exactly how class D functions. But nothing is 100% efficient. That heat sink is there for a reason, in this case to dissipate the roughly 10% of waste energy created by the class D switching transistors in their overlap period. It is seriously undersized even if you assume 95% efficiency, which is stretching the limit of even class D amplification. It is an obvious weak point of this unit’s design.
@@artysanmobile For a class D 10% is very high. That said no-one runs an amplifier at full rating. A 50W amplifier really runs at 5W 99% of the time otherwise the music playing sounds like crap. It is a question of dynamic range. Music has at least a 10 to 1 dynamic range for acceptable reproduction and 100 to 1 for any real fidelity.
Allan Gibson None of that has any bearing on my complaint re design. Proper engineering takes into account, within financial constraints, the absolute worst case scenario, and then generally a margin is added to that. I know this isn’t exactly life or death here, but the design is pointlessly doomed to eventual failure by that one silly decision. If you rate your amplifier for 100W of output to a given load, you design it to do that indefinitely, not ‘maybe if someone’s listening to music properly’. Specifications mean something to many manufacturers. To some, they are just sales tactics.
That's what I was thinking. I mean, yeah sure, not much than can go wrong just reconnecting the headers, but regardless, if doing a review, test the product as it came, THEN take it apart.
If you can't take something simple apart and put it back together... then it obviously has build quality issues. Your provided evidence defeated your own argument. I am pretty sure that is where the origin of the word moron came from.
Yeah well normally you expect these JST connectors to be quite reliable, you can take them out and put them back in a bunch of times. Either there's a solder joint problem or a bad crimp on the cable, or bad fake connectors. Given that, it's not really necessary to disassemble it to get it to fail, normal China Mail can do it all for you! But it's also not a major issue for a technically inclined, it's just the wiring and there isn't a ton of it, and i mean when you order something so cut throat priced, it's going to come with compromises. They really aren't getting a lot of profit out of this thing!
It is no doubt a class-D output. The efficiency may be as high as 95%. Still at 100W that makes for about 5W of heat to get rid of . The heat sink won't do that. A good rule of thump is 1 square inch of fins in the open air can get rid of about a Watt.
For the cost, size, and power rating it has to be class D. Although great strides in SQ have been made with class D amps I think I would still rather have 40w of good class A power. Hell, if they made one of these with class A circuitry I could also use it to keep my coffee warm at my desk. Win/win where I sit.
Most decent level audio seems to be around 2W if you measure it on a scope, for general usage I suspect it won't get too hot - it will also have thermal protection built in the chip.
The internal audio/LGR connector housing looks like it's mostly pulled off at 7:24. That might be the source of the audio crackling / connectivity issue - if the pins aren't fully engaged in the connector, you'd get exactly the problems you had. That style of connector can be a real pain to unplug - I'm wondering if it came loose in the disassembly?
The pins are still attached to the board, yeah. But if you plug the connector into the housing, and it's still not properly seated on the pins, it'll make poor contact. Which is kind of the opposite of fine.
@@randyglenn5965 So, the shroud gets pushed back into place, NBD. It is totally unnecessary to assume the reviewer is completely incompetent: I appreciate that the reviewer put some effort into this review, and don't think comments of the kind you are making are going to encourage more videos of this kind, from anybody.
If you can point to where in my comment I assumed he was "completely incompetent", feel free. More likely, you'll only find the part where I pointed out something that it looks like he missed. People miss things sometimes. It happens.
I’m one of those people with a pi setup and can confirm the dirty audio comment! I’ll be picking up one of these guys for my pi setup and use the power out from the computer monitor I’m running because it has detachable powered speakers. This little guy will be the answer to my audio situation. The crackling you heard was because the connection to that front board wasn’t fully seated, and since it lives inside the case(it’s a simple fix). I just slightly/minutely bend those pins in one direction to tense them up & problem solved! I also have added a small bit of solder to said pins to make them bulkier and thus give a much proper connection in other applications with such connectors. Though I doubt that is necessary in your case. Maybe drilling some tiny holes to the back or under the case(near that heat sink will prolong the life of the amp in the long run. Cheers ;)
I picked up mine on Amazon for about $32 and it came with accessories. It works like a dream without the sound problem you experienced. But it shows up as MINIAMPL on my computer.
20:28 - Kitty sighting! Interesting review, and good catch on the caps. I think DJ Firestorm made a valid observation concerning testing "out of the box" before disassembly, but man... As Archer might have said, "Phrasing!"
I bought this amp and i´m happy with it. Stable and quick pairing on bluetooth and good sound. Even better when connected via USB on my PC. Much better than using wired 3.5 plug connection from onboard sound chip. I didn´t bought it with those too weak transformers. I chose only the amp for about 16€ and use one of the 24V transformers of other mini amps i have. But even if you choose to buy an extra 24V 5A transformer for 8.99€ you get the best results for together 25€! I love this small amp!!!
7:27 - Aside from the uncleaned flux residue, the ground pin on the connector daughter board is cold soldered. You clearly had intermittent connections when you were testing the bluetooth interface. 11:19 - This unit is false advertising 2 X 50W capability. Its own documentation says it will run on 9V to 12V. According to the data sheet, the amplifier cannot produce more than 2 X 15W, and that is dependent on the available current of the power supply. Further, there is no way that little stick-on heat sink can dissipate even the 30W, particularly with no ventilation. A little math: Class D amps are, at best, 90% efficient. 8 ohms across 12 volts at 90% efficiency is 16.2 watts per channel.
I remember buying a brand new Mercury Lynx( Escort) 5 door hatchback in 1982 and it DID NOT come with a radio. They wanted extra for one and I said NO. My point is , I went to K- Mart and invested in what was back then, A top of the line stereo with built in amplifier. It had some sliders and rows of lights. Back then, it was a very high end system and sounded better than any Ford radio. I added my own boost and base that was mounted in the back corner of the car. I could knock the back seat all the way down by pulling the seat bottom. It was never advertized, but that feature made that car priceless in my book. I hauled so much stuff in that car as well as camped in the back of it. That amp reminds me so much of the one I had in my car. Great memories of the 80's. Huey Lewis and the News and the Police were my favorite two groups then.
Someone spent a few cents extra on 105° centigrade rated capacitors. This bodes well for the whole design, built up to a standard rather than down to a price :)
I have a no-name 2x120W chinese amp from Aliexpress on my balcony. I feed it 24V from an old Compaq Rackswitch PSU that can give 7A @ 24V. The amp pushes out nice sound, even with full size speakers. Has line in, and Bluetooth with a physical switch. Picked it up during one of the New Year sales for $50 shipped. I've had it now for about 3 years, using it a lot during summer, and not so much during winter. Guests cannot believe that the amp is so small, but outputs the quality and volume it does. :) Some of these amps are nice, others, not so much. Thanks for the video. Greetings from Norway.
1:00 I had to modify a 2.1 amp using the cut track method, as the subwoofer channel had an independent volume control that wasn't controlled by the main volume. No idea why you'd design something like that...
Mini "D", as in Class. As for wattage, well, it's all Ohm's Law. You can run a full-scale sine wave into the USB or BT input, then measure the RMS voltage coming out of the binding post. From there, it depends on the impedance of your speakers -- which, being a reactive load, the resistance will vary by frequency. Since these have been heavily modified, you won't know the nominal impedance, and it's not going to be the same thing as DCR. Unless you have a dynamic testing rig (Dayton Audio makes one called DATS that is really inexpensive) then you'll have to make do with theoretical calculations. TI generally say what they mean, and mean what they say. If they say it will do 50Wx2, it will -- and they'll tell you under exactly what conditions that will be the case. But it may not be practical due to heat or power supply constraints. Engineering is compromise. Lastly, in my opinion, the "modularity" of this thing isn't indicative of well thought-out design and serviceability. It's just the most expedient and cheapest way to do it. Especially things like the binding posts using PCB holes. So much cheaper to assemble than wiring. It would also be difficult to get that front 3.5mm jack on the same plane as the rest of the components, so it gets its own adapter PCB. I guarantee they weren't thinking of your ability to repair it, they were just optimizing out the cost of doing it any other way.
I have used one of those little Nobsound amps on my desk for almost 2 years and it works great on Bluetooth or as a DAC for PC sound. It's about 20w per channel and powers my bookshelf speakers just fine.
The worse part about the cap leads is that the proper practice is to cut the leads to length prior to soldering, so it wasn't even a 'couldn't reach' issue, just straight laziness lol
Or, that capacitor lead length might also could be serving as heat sink for the cap, extending the life of the cap just a little tiny bitty bit. It would be more applicable in a switching power supply where those caps bulge, leak and blow chunks as their ESR goes up and up... That's the main failure w/ MOBOs, & especially LCD Monitors.
You’re right! I hate that font since I wrote documentation in the late 80s and that font was recommended. Especially since we had to follow certain numbering rules where the number one or the letter l made a big difference and both could stand just beneath each other. On the Olivetti typewriter I used the l and the 1 where actually the same letter on the wheel.
With its PCB design, 4 big audio connector work as big heat sink, better than its tiny heat sink. With an efficient switching amplifier, I would not worry about heat dissipation.
Class D, the future of commercial designs - ~90% efficiency, small heatsink seems to be 'OK'. Also break the connector, complain about build quality :D
90% “theoretically” efficiency. I have yet to see just “One” class D amp that actually deliver what people expect from the specifications. Even professional build class D amps that promisses like 1-2k watts into 8 ohm usually gets utter blown away by a well constructed 30 year old class a/b amp of 1-200 watts with a 15kg transformer in the psu. Class D is only good for cheap solutions where real muscles for continous High power load isn’t really needed. That doesn’t mean that its completely useless tho, you just can’t expect anything at all from these kind of china electronics. You might get possitively surprised sometimes tho. But in most cases Its more than adequate for driving those old car speakers out in the Working shed or for a cheap bluetooth speaker for your phone.
-Yesss a video showing a person not working with 240V that means he cant work dangerously with bare wires while the things powered on. -UA-camr proceeds to rip the thing apart before testing it and then blames the device. fuck.
You should have tested the amp BEFORE opening it. Now we'll never know if it sounded like that out of the box or you just broke something while poking the insides.
Thank you for the video. You should've played music on it first before disassembling it. You might break it yourself. Yet again, what do you expect from a $20.00 device?
Thanks for the video! I don't know much about electronics and depend on guys like you to steer me in the right direction. I just bought one and hope it will solve the problem using my tablet in my shop. Regards
Sounded pretty good, I'm building a BT speaker for my inlaws for Xmas it will be run off a small car jumpstarter rechargeable unit, it hat BT, has USB input and charging output, I'm building in a Google home mini, all invaded in a WW2 ammo box. Led lighting around all the speakers via some 3mm perspects and tiny sound active lights. I need to have 12v output, 9v &7v so I picked up a couple of tuneable voltage boards. Small amp, I'm running a central 6inch 3way speaker and 2 sets of 2way and tweeter speakers. It has USB input plus 2 USB charge outputs, 3mm headphone jack input. So I've got my self drawn up wiring diagram and will see how it's all going to run....... I've built it about 100 times in my head, done dozens of sketches of the final product, I'm waiting on 1 more part then I think I'm up and ready to get it started........ Hoping all my calculations and ideas will work. It's to run outside by their pool and spa, so I'm trying to build it all 100% hands-free so the can"hey google" any changes, being music changes to volume control....... So fingers crossed......... At least the small jump starter battery supply will last a long time and takes over night to charge from zero to 100%. But when it's off and not in use, it will just look like an old WW2 ammo box....... I'm going for the, in wrap disappointed face to the open the box and wow face...... Just need my last 2 components to start wiring it all up to see if it will work be4 I go mounting and soldering everything...... Thanks for your upload, gave me more food for thought.....
I had a car audio Bose 1401 system derived from 901 drivers. They look EXACTLY like the same full range drivers. The 1401 was 100 watts total into 4 speakers. It was actually good stuff...for the 1980's.
Timely! Bought it. Yes, for the garage! Will test w/o disassembly. So... FYI, the datasheet for the TPA3116 Power Amplifier Chip has a linear power out with voltage. 16v goes 15/30w into 4/8 ohm, 24v goes to 35/70w into 4/8 ohm. Should be plenty loud.
Got it, everything tests out, all 3 inputs ok. Drives even big floor speakers. I used a lab power supply and basically, the voltage doesn't matter. Draws more amperage at lower voltage but same volume (class D! should have known that). 0.2 amp will get you quite a bit of sound. Thanks Colin!
If it hasn't got a micro chip, you're not interested. Bring back all discrete stereo amplifiers with massive power supplies. Those things always sounded better to my ear.
If you touch a circuit board without an antistatic wrist strap attached to a ground, then you can introduce 20,000 volts or more of static electricity. It only takes 7 volts to destroy some chips. Also work on an anti static mat. Always check the unit before you disassemble it, then you can narrow down the problem cause.
I vote "hidden Gem." I bought one too. No issues with mine. I have it feed by a 20 volt laptop power supply that can put out 3.25 amps. I am using Paradigm Mini Monitor speakers and all in all I am very satisfied. I suppose I could get more power if I used a 24 volt supply with a higher amp rating but it has plenty of volume for the 15' by 20' room it is set up in, and it does not seem to have any heat issues after a month of being used daily.
@@maxlever Miniamp1. Towards the end of the video he tells you the best way to search EBay to find it. There are at least half a dozen sellers that sell it. I bought mine for roughly $18 from a state side distributor and had it within 4 days.
For those who like to take apart things.... Always try the product first then tear it apart and play. That way you have something to reference back to. like did it work before I tore it apart.? Now you won't know. Great video though thank you.
It's doesn't have a butchered printed text "Miniamplifier" across the top, it's "Miniamp1"...with the number "one" at the end. Widely used rebrand OEMs like the OEM that made this mini-amp aren't too terrible since they have to meet some requirements set forth by retailers looking to sell their wares. If they missed the English portion of it, I would've expected the overall quality to be way worse. Speaking from a Chinese commerce and importer's point of view.
I wanted a little amp for the workshop. Had already looked at the model shown before. Your video animated me to buy now. The functions and the quality that was justifiable for the price were the deciding factors. Thanks a lot! It will replace a heavily modified and run-down WEGA ADC-2 (1978!).
I think he has NOT damaged it and the problem with the noise (only!) with bluetooth has nothing to do with opening the device (without testing it before). It can also be a design-problem because of missing (or not good enough) ground around the BT chip or antenna. If you have the same problem with noise via BT just touch the chip or its contacts with your finger, the noise often will stop. I was searching "hours" for the reason of this noise on my amplifier and finally found it. I fixed it with a little bit of paper (as isolator), aluminium and a short cable to ground. If you have still noise problems, replace the powersupply with a battery and verify. Sorry for my (bad) english, I'm german.
Have you come across the CMoy amplifier in your investigation? It's an internet design made available for anyone. You can breadboard it, make your own PCB, buy a kit, or buy pre-made units from individuals. I bought one of them years ago which uses a rechargeable 9V and a DC jack, the sound quality is AWESOME. These days you can get ones which charge off USB. Strong recommend on CMoy amplifier if you can find one.
At 3:57 the LGR connector is attached to the board, after you remove it at 4:04 the connector is broke from the board. Then you complain about the short you created like it was the manufacturers fault after you put it back together. Using the proper tools to remove the connector instead of yanking on it might have prevented the damage.
i built one on a breadboard with a TCA0372 1A dual opamp which i recycle from an old table top cd player. i think the fun part is when i realized i got the calculation right when i hook up to an oscilloscope and no magic smoke.
Perhaps they tuned those cap lead lenghts to act as RF chokes for a specific harmonic frequency of the PWM amp in order to minimize ultrasonic distortion ? ;)
@ i didn’t say inductor. They are certainly antennas, and hence their propensity to attenuate (or, “choke”) any rf energy that is matched to the impedance of those lead lengths (hence my “ultrasonic” comment). I had put a “;)” but I guess you missed it 😛
@ I actually said “act as…”Cognitive dissonance harder 😝 Aren’t you up on how RF antennas work? Hint: they radiate energy optimally at a specific frequency. Google “simple RF notch filter”.
What are the BOSE full range speakers like at over 10 khz? How to make an amazing full range speaker sound (with the extra khz). Make a pair of extremely thin sticks that are also very short sticks (only like 2 mm tall, made out of a split toothpick). Then glue each stick onto the dust caps of the FR drivers and stick a tiny piece of (coffee can seal) foil onto the ends of the sticks. Cut the foil pieces in a teardrop shape like 1/4" x 1/8" big. I suggest you prick a hole in the tiny foilies to make them easier to glue onto the ends of the sticks. It's REALLY TEDIOUS but really cheap and your full range speakers will STING like crazy in the top end. It's acoustic separation technology, the foily is vibrating completely independently of the dust cap, and that is the big secret. If you attach the foily directly to the dust cap you get NO WHERE NEAR the effect. When it's on the end of the stick, acoustically it's like a miny 2-way coaxial driver, giving the top end a completely separate vibration to the main cone. And this extends the highs way better than just sticking the foilie directly to the dust cap.
Remember Class-D amplifiers are very efficient (90% or more) and at normal non-party conditions it doesn't produce any (extra) heat. You mention it is the Texas Instruments TPA3116 , it starts to produce 'heat' (a little warm) when you feed it above 12 volts. You can also power the TPA3116 with only 5 volts (if there is no voltage requlator inside this that requires a higher voltage), I have a few boards that works nicely on 5 volt (USB power) and if you use decent speakers (hook up 100W kenwood, 96db 1W, Wattage don't say everything - sensitivity and construction matters) , it is very suitable to use at computer, garage, etc to use at normal (and pretty loud) listening conditions. 1W, 3W or 5W can be very loud when using a pair of decent speakers, especially using Class-D amplifiers. The TPA3116 is really a good and efficient chip because of the wide input range and decent crisp quality of sound, even on a low(er) voltage. I like to see if it is possible to run it at usb power, I think it is possible besides the required input specs. You didn't try the USB input connected to a computer, I think (by experience of JL 'branded' chips) that there are some hidden features.
The heat-sinked IC on the back board is likely a class D amplifier (switch-mode outputs). This is re-enforced by the inductors present on the each of the speaker terminals.I don't think overheating will be a problem.
Class D isn't magic. Yes, its a lot more efficient (90-95%) than typical class AB (65%), but it still has to dissipate some heat and that is very tiny heatsink in an enclosed space with no path to outside.
@@goatofpower True, there is no magic. However, the heat produced depends on how hard you drive MOSFET gates, and how fast the MOSFETS switch between off and on states. That switching time is where most of the heat is being produced. Minimize the switching time, and you minimize the heat produced.
We'll never know if your disassembly caused the problem or not. I really wish you and other reviewers would test first and THEN disassemble. Is it possible it's name is Mini Ample?
I've got one of those for about a month now, brilliant in nearly every way, except one thing that makes me mad each time : the voice volume (and the litte audio jingle at startup) is insanely high and i can not find how to modify it. Yours doesn't seem to have this voice over and jingles, it's kinda weird.
I see that he pulled the plastic housing off.. and probably didn't push the connector all the way back in when he re-assembled it... another reason why you need to disassembly it... AFTER testing it!
Hand drill a grid of small holes through the top bottom near the chip. Add a bigger piece of metal on top of the other. The googlnet can tell you what adhesive is decent for cheep. Have fun with it. Make a slightly larger enclosure that has the above features and say it's a custom built amp just for garages. Bend an old gas can or put it in a cigar box. My brother-in-law user to do stuff like that in our shop. We'd take the speaker-loaded front panels and staple them into large cardboard boxes of "correct" volumetric size and A-maze our friends. Fun is fun!
My brother made a killing back in the 70's building custom speaker boxes using particle board and speaker cloth. We would salvage speakers out of old stereo units and he would sell eather custom built preinstalled or you could choose from a list of Radio shack speakers. He sold a ton of those before getting bored with it. I believe it financed his first car. 1970 Duster. Those were the days. I am restoring old lawn mowers to finance a Conversion van right now.
OK .... so I am old and remember the massively heavy amps that were common in the late 70s. Good thing with them is after several decades of working flawlessly, they atleast made a great doorstop or weight for holding down wood projects as the glue dries 😁 Much agreed on Test them Dismantling idea. Wish those with Amp Dynos would start testing more of these budget D class amps to see if they meet claimed outputs. Worst case you have a light duty use Paperweight if all else fails
Actually, I think the metallic contacts act as the heat dissipaters, they are big enough and get rather hot while the amplifier works - though they do not touch the chip directly. The sound level bar is absolutely useless: I just put a sticker on the green/yellow region and can only see two red indicators. :-) P.S. Just discovered that it is possible to hook up Sumsung s7 to this device via a MiniUSB adapter and use it as an audio amplifier for the phone. The S7 has recognized the device immediately. UPDATE. A couple of days of good work and now the sound in one of the channels disappears in about 20 minutes after being switched on a insignificant load. It looks like the heat affects the soldering somewhere inside.
@@Mr.Leeroy Mmm, no, most laptop chargers, at least in the US, only use hot and neutral. The reason it might introduce distortion is because PSRR is typically only good in amp chips when the noise isn't high frequency. However, some people, particularly those who like trance misc, like the more lively treble distortion that results. Purists would never settle for it though, want it to sound the way it's supposed to without that coloration.
he would destroy your reputation before he even knew if your product works. what a horrible idea. this video makes me want to start a channel and do it the right way and even test the same stuff he broke just to prove his channel should be delete
@@djfirestormx thanks. You are right. Tho if you start a channel I'd be happy to give you stuff I make for review :) So far I've been designing amps. Now I'm working on consumer affordable room correction system. One of my customers is begging me to design a pair of speakers for him so I'll also give that a try.. I might start a company soon :)
Your craftsmanship and quality would speak for itself. This dude is pretty honest and knowledgeable. Would you rather have some hot head like DJ storm reviewing your product? He’d probably call for your execution if he didn’t like it. Use some common sense here
Nálam az iLike bluetooth hangszóró adott ki ilyen hangot, mikor is a bluetooth vevőegység bezavarta a végfok IC hangkimentét. A megoldás nálam az volt hogy egy kis méretű csavaralátétet ragasztottam a tekercs tetejére, és a zaj megszünt.
I got the LvPin 2.1 hooked up to two NIB SET OEM 6x8 Genuine Ford Speaker XC2F-18814-BA with GRILLS 25 WATT 4OHM and one 8" subwoofer all installed into a plastic cooler and I just plug it into my cig lighter it blasts me out of car!
Personally, I'm not sure if I'd buy something like that given that I have a USB DAC on my mixer console. For what it is though I could see people actually wanting this. You should have a look around Ali Express's website and Amazon too. Often the sellers of such devices have a store on those sites too. In fact, sometimes that's where people get them to sell on eBay. Great video... Liked & Subbed
This review is 100% garbage. You evaluated it AFTER you opened it up and you didn't even test it BEFORE you opened it up. You clearly broke connectors doing it, and then now users watching this will NEVER know if they have QC issues or your just an idiot. Vote this channel for worlds worst channel ever
Vote this channel for worlds worst channel ever ?? ... -___- Dude relax, snickers?
@@heliopijpe I love how This Does Not Compute even pinned this haha
asrgaqgq sdfgsdgsdfgsdg Yeah, it’s pretty rich
DJ FireStorm Your comment is a lot like the item under review. Thanks!
Goose Frabba
Based on your review I bought one of these and set it up in my shop so can listen to music, etc. from my tablet.
I hooked it to 2- 30w speakers 20' apart across the room and couldn't be happier! Clean rich sound and no distortion that I could perceive and more volume than I will ever use.
As a bonus, I discovered that it turns itself off after a period of nonuse!
Thanks for this review!
It has made the time I spend in my shop more enjoyable.
Regards
You should really test to see if it works before you open it up. As viewers we have no way to know if it was you or the build quality.
Was gonna say the same thing!
Yeah he very well could’ve wiggled loose one of those connectors while he unplugged them.
It's not like he abused it taking it apart... and it essentially was only 12 easy to access screws anyway... highly doubt it was anything he did. Even if it were something he did, it would have only happened if the build quality were low.
Right he tore it apart then blamed the nois on the build quality. Maybe it was his takeing it apart.
@@wardraven8755 If you can't take something simple apart, then it is build quality... how are you not seeing this?
You are right about the single chip doing everything, it's a quite powerful microcontroller (32 bit and up to 160MHz operation), with built in radio receiver/transmitter for bluetooth. Manufactured by ZhuHai JieLi Technology Co.,ltd. Often they can do bluetooth, read sd cards and playback of mp3, depending on the programming and the particular IC version. A lot of them also have the dreaded 'The bluetooh device is successfully connected' voice that plays at full volume and in a dodgy Chinese accent. They are found in the mini mp3 players and generic bluetooth speakers.
Can we flash those chips?
@@Kiana.Da.Editor.3701 yes and cycle back with own personalised messages😉
Thanks for the extra information. I already have a speaker which says "The bluetooth device is sucessfully connected" LOL. It still mkes me jump.
Would love to see a amp with all the features on a cheap little amp. Might even be a good component system on the cheap
At 3:54, when you first took it apart, you can clearly see the LGR connector is fully seated on the PCB. At 18:13 it's plain to see the connector is jacked up off the PCB by a good 3mm. This is not a build quality issue, had you not taken it apart it would be working perfectly.
I deal with these connectors regularly and they are perfectly suitable for this purpose. They are not flawed when it comes to initial assembly, build quality, or careful servicing.
They are, however, not foolproof when it comes to servicing. Some attention to detail is required.
Was just going to say this but you did already
Good Spot!!!! +1
In other words he made a fool of himself, LMFAO!!!
M is the muting pin. The front board is the preamp, and the back board is the power amp. The signal on the M pin shuts down the power amp to prevent pops and clicks at power on/off and when changing sources or modes.
(well, it's supposed to anyway...)
so the main amplifier is at full volume all the time and you only adjust the volume of the preamplifier (board/chip) and that signal is sent through LGR connector to the amplifier.
@@orange11squares Yes, that is pretty much how all amps work. When you set your vol. control to max, you are essentially removing all resistance between the input signal and the amp. Full input signal to amp = max volume.
ALWAYS test before disassembly. That is, if you want an ACCURATE review of a consumer's experience with product, as shipped. Once you dig into something, you taint the review.
BTW: That is 50 Watts Peak Power with ampl amounts of distortion.
Sam Houston Assuming a very generous 90% efficiency, that fingernail-size heatsink is expected to dissipate 10W? Um, no... Great idea, horrible execution. If disassembly/reassembly as shown breaks it, no thanks.
@@artysanmobile Class D amplifiers have very low power dissipation. The output driver is either hard on or hard off. No analog modulation occurs, it is just feeding a very high frequency square wave to the speaker with pulse width modulation.
Allan Gibson I know exactly how class D functions. But nothing is 100% efficient. That heat sink is there for a reason, in this case to dissipate the roughly 10% of waste energy created by the class D switching transistors in their overlap period. It is seriously undersized even if you assume 95% efficiency, which is stretching the limit of even class D amplification. It is an obvious weak point of this unit’s design.
@@artysanmobile For a class D 10% is very high. That said no-one runs an amplifier at full rating. A 50W amplifier really runs at 5W 99% of the time otherwise the music playing sounds like crap. It is a question of dynamic range. Music has at least a 10 to 1 dynamic range for acceptable reproduction and 100 to 1 for any real fidelity.
Allan Gibson None of that has any bearing on my complaint re design. Proper engineering takes into account, within financial constraints, the absolute worst case scenario, and then generally a margin is added to that. I know this isn’t exactly life or death here, but the design is pointlessly doomed to eventual failure by that one silly decision. If you rate your amplifier for 100W of output to a given load, you design it to do that indefinitely, not ‘maybe if someone’s listening to music properly’. Specifications mean something to many manufacturers. To some, they are just sales tactics.
18:20
>Takes apart amp
>Reassembles amp
>Breaks amp
"IT MUST BE THE BUILD QUALITY"
That's what I was thinking. I mean, yeah sure, not much than can go wrong just reconnecting the headers, but regardless, if doing a review, test the product as it came, THEN take it apart.
You guys really aren't gonna like AvE..
If you can't take something simple apart and put it back together... then it obviously has build quality issues. Your provided evidence defeated your own argument. I am pretty sure that is where the origin of the word moron came from.
@@jong2359 I only see one moron here
Yeah well normally you expect these JST connectors to be quite reliable, you can take them out and put them back in a bunch of times. Either there's a solder joint problem or a bad crimp on the cable, or bad fake connectors. Given that, it's not really necessary to disassemble it to get it to fail, normal China Mail can do it all for you!
But it's also not a major issue for a technically inclined, it's just the wiring and there isn't a ton of it, and i mean when you order something so cut throat priced, it's going to come with compromises. They really aren't getting a lot of profit out of this thing!
For the LGR connector it was completely flush with the PCB, you yanked it out a few mm of the board after disassebling it.
It is no doubt a class-D output. The efficiency may be as high as 95%.
Still at 100W that makes for about 5W of heat to get rid of . The heat sink won't do that.
A good rule of thump is 1 square inch of fins in the open air can get rid of about a Watt.
Thump? Yeah, probably...
For the cost, size, and power rating it has to be class D. Although great strides in SQ have been made with class D amps I think I would still rather have 40w of good class A power. Hell, if they made one of these with class A circuitry I could also use it to keep my coffee warm at my desk. Win/win where I sit.
@@Thezuule1
It would be about a foot on a side to get enough surface area
@@kensmith5694 Yeah but you're not factoring in the heat dissipation from my coffee. ;)
Most decent level audio seems to be around 2W if you measure it on a scope, for general usage I suspect it won't get too hot - it will also have thermal protection built in the chip.
One thing to point out, is that the solder residues are still there, the manufacturer of the PCBA´s didnt really care about quality.
I think it says "Miniamp 1." Old typewriters required using the lower case "L" for 1.
“Greetings im a amplifier connector” and this is another amplifier thing” 😂
Took me a while but I got there 😆
Plsssss keep doing this Amps reviews, they are great, its cool having a channel to learn audio and all that stuff!!
The internal audio/LGR connector housing looks like it's mostly pulled off at 7:24. That might be the source of the audio crackling / connectivity issue - if the pins aren't fully engaged in the connector, you'd get exactly the problems you had.
That style of connector can be a real pain to unplug - I'm wondering if it came loose in the disassembly?
ya see how he unplugs these? 4:00 wot a scrub, just twists em off ay
The pins are fine, only the shroud has moved, so don't panic. Everything is fine.
The pins are still attached to the board, yeah. But if you plug the connector into the housing, and it's still not properly seated on the pins, it'll make poor contact. Which is kind of the opposite of fine.
@@randyglenn5965 So, the shroud gets pushed back into place, NBD.
It is totally unnecessary to assume the reviewer is completely incompetent: I appreciate that the reviewer put some effort into this review, and don't think comments of the kind you are making are going to encourage more videos of this kind, from anybody.
If you can point to where in my comment I assumed he was "completely incompetent", feel free. More likely, you'll only find the part where I pointed out something that it looks like he missed.
People miss things sometimes. It happens.
I’m one of those people with a pi setup and can confirm the dirty audio comment! I’ll be picking up one of these guys for my pi setup and use the power out from the computer monitor I’m running because it has detachable powered speakers. This little guy will be the answer to my audio situation. The crackling you heard was because the connection to that front board wasn’t fully seated, and since it lives inside the case(it’s a simple fix). I just slightly/minutely bend those pins in one direction to tense them up & problem solved! I also have added a small bit of solder to said pins to make them bulkier and thus give a much proper connection in other applications with such connectors. Though I doubt that is necessary in your case. Maybe drilling some tiny holes to the back or under the case(near that heat sink will prolong the life of the amp in the long run. Cheers ;)
Class D, a swithcing mode amp. It does not need a lot of cooling due to its high efficiency
In noise and interference.
I picked up mine on Amazon for about $32 and it came with accessories. It works like a dream without the sound problem you experienced. But it shows up as MINIAMPL on my computer.
Mini “D” Amp
As in class d amp.
Yep, I thought that was pretty obvious too
Jawohl!
Next time test it before taking apart and breaking it !!
20:28 - Kitty sighting! Interesting review, and good catch on the caps. I think DJ Firestorm made a valid observation concerning testing "out of the box" before disassembly, but man... As Archer might have said, "Phrasing!"
I bought this amp and i´m happy with it. Stable and quick pairing on bluetooth and good sound. Even better when connected via USB on my PC. Much better than using wired 3.5 plug connection from onboard sound chip. I didn´t bought it with those too weak transformers. I chose only the amp for about 16€ and use one of the 24V transformers of other mini amps i have. But even if you choose to buy an extra 24V 5A transformer for 8.99€ you get the best results for together 25€! I love this small amp!!!
I suspect the speaker terminals and wires will dissipate way more heat than the heatsink.
7:27 - Aside from the uncleaned flux residue, the ground pin on the connector daughter board is cold soldered. You clearly had intermittent connections when you were testing the bluetooth interface. 11:19 - This unit is false advertising 2 X 50W capability. Its own documentation says it will run on 9V to 12V. According to the data sheet, the amplifier cannot produce more than 2 X 15W, and that is dependent on the available current of the power supply. Further, there is no way that little stick-on heat sink can dissipate even the 30W, particularly with no ventilation. A little math: Class D amps are, at best, 90% efficient. 8 ohms across 12 volts at 90% efficiency is 16.2 watts per channel.
I remember buying a brand new Mercury Lynx( Escort) 5 door hatchback in 1982 and it DID NOT come with a radio. They wanted extra for one and I said NO. My point is , I went to K- Mart and invested in what was back then, A top of the line stereo with built in amplifier. It had some sliders and rows of lights. Back then, it was a very high end system and sounded better than any Ford radio. I added my own boost and base that was mounted in the back corner of the car. I could knock the back seat all the way down by pulling the seat bottom. It was never advertized, but that feature made that car priceless in my book. I hauled so much stuff in that car as well as camped in the back of it. That amp reminds me so much of the one I had in my car. Great memories of the 80's. Huey Lewis and the News and the Police were my favorite two groups then.
Getting old is a bummer 😒
Someone spent a few cents extra on 105° centigrade rated capacitors. This bodes well for the whole design, built up to a standard rather than down to a price :)
"MiniDamp"
a small moisture
Mini Dick Amplifier?
Shame on you lol
Was I the only one that read it as mini-d-amp? As in, mini d-class/digital amplifier.
Mini Class D Amp?
Did not work underwater, but it did bubble.
I have a no-name 2x120W chinese amp from Aliexpress on my balcony. I feed it 24V from an old Compaq Rackswitch PSU that can give 7A @ 24V. The amp pushes out nice sound, even with full size speakers. Has line in, and Bluetooth with a physical switch. Picked it up during one of the New Year sales for $50 shipped. I've had it now for about 3 years, using it a lot during summer, and not so much during winter. Guests cannot believe that the amp is so small, but outputs the quality and volume it does. :) Some of these amps are nice, others, not so much. Thanks for the video. Greetings from Norway.
13:03 You don't have speaker cables twisted like that, it acts as an inductor and consequently a loss of highs. You should know that.
This is not a coil; short intertwined wires have no audible influence at all.
How much RF do you think is prevented by doing this?
Welcome... to another LGR thing! (I heard it in Clint’s voice when I saw that plug)
1:00 I had to modify a 2.1 amp using the cut track method, as the subwoofer channel had an independent volume control that wasn't controlled by the main volume. No idea why you'd design something like that...
Mini "D", as in Class.
As for wattage, well, it's all Ohm's Law. You can run a full-scale sine wave into the USB or BT input, then measure the RMS voltage coming out of the binding post. From there, it depends on the impedance of your speakers -- which, being a reactive load, the resistance will vary by frequency. Since these have been heavily modified, you won't know the nominal impedance, and it's not going to be the same thing as DCR. Unless you have a dynamic testing rig (Dayton Audio makes one called DATS that is really inexpensive) then you'll have to make do with theoretical calculations.
TI generally say what they mean, and mean what they say. If they say it will do 50Wx2, it will -- and they'll tell you under exactly what conditions that will be the case. But it may not be practical due to heat or power supply constraints. Engineering is compromise.
Lastly, in my opinion, the "modularity" of this thing isn't indicative of well thought-out design and serviceability. It's just the most expedient and cheapest way to do it. Especially things like the binding posts using PCB holes. So much cheaper to assemble than wiring. It would also be difficult to get that front 3.5mm jack on the same plane as the rest of the components, so it gets its own adapter PCB. I guarantee they weren't thinking of your ability to repair it, they were just optimizing out the cost of doing it any other way.
I have used one of those little Nobsound amps on my desk for almost 2 years and it works great on Bluetooth or as a DAC for PC sound. It's about 20w per channel and powers my bookshelf speakers just fine.
This might be a good option for a small, portable, boombox kinda thingy I'm planning. Appreciated.
grab a nobsound branded mini amp :D
Dave J. would be proud, mate! Also, yech! Look at all the vapour skidmarks from that horrendous lead-free solder...
Been seeing this quite often in aliexpress. Glad you reviewed it in depth for me to decide
man, this is bad test, wheres the "Bass, I love you" tested out? 😁 thank you for testing and tearing it out 😉
The worse part about the cap leads is that the proper practice is to cut the leads to length prior to soldering, so it wasn't even a 'couldn't reach' issue, just straight laziness lol
Or, that capacitor lead length might also could be serving as heat sink for the cap,
extending the life of the cap just a little tiny bitty bit. It would be more applicable in
a switching power supply where those caps bulge, leak and blow chunks as their
ESR goes up and up... That's the main failure w/ MOBOs, & especially LCD Monitors.
Miniampl lol I think it's supposed to be Miniamp1 :-)
You’re right! I hate that font since I wrote documentation in the late 80s and that font was recommended. Especially since we had to follow certain numbering rules where the number one or the letter l made a big difference and both could stand just beneath each other. On the Olivetti typewriter I used the l and the 1 where actually the same letter on the wheel.
Yea I think so too!
And on the Bluetooth front : Mini D (class) amp, Minidamp
The bottom of the device also states the model name as "Miniampl" in a much more reasonable font, so it really is an L, haha.
Of course...
With its PCB design, 4 big audio connector work as big heat sink, better than its tiny heat sink. With an efficient switching amplifier, I would not worry about heat dissipation.
Thats a good point, as long as it has nice big thick tracks to the connectors.
thanks for making this video, i thought these were really sketchy ones but it is apparent that theyre actually pretty good
Sincerely enjoy your content. You've pointed out another item I don't need, but now want! Haha. Great stuff, keep up the awesome work.
Class D, the future of commercial designs - ~90% efficiency, small heatsink seems to be 'OK'.
Also break the connector, complain about build quality :D
90% “theoretically” efficiency. I have yet to see just “One” class D amp that actually deliver what people expect from the specifications. Even professional build class D amps that promisses like 1-2k watts into 8 ohm usually gets utter blown away by a well constructed 30 year old class a/b amp of 1-200 watts with a 15kg transformer in the psu. Class D is only good for cheap solutions where real muscles for continous High power load isn’t really needed. That doesn’t mean that its completely useless tho, you just can’t expect anything at all from these kind of china electronics. You might get possitively surprised sometimes tho. But in most cases Its more than adequate for driving those old car speakers out in the Working shed or for a cheap bluetooth speaker for your phone.
Do you think the problem was because it was taken apart?
Ya, I would have tested it BEFORE I ripped it apart.
YES - the video actually shows the condition of the front audio connector was compromised by the brutal way this idiot tried to disassemble the thing.
-Yesss a video showing a person not working with 240V that means he cant work dangerously with bare wires while the things powered on.
-UA-camr proceeds to rip the thing apart before testing it and then blames the device.
fuck.
You should have tested the amp BEFORE opening it. Now we'll never know if it sounded like that out of the box or you just broke something while poking the insides.
It was likely halfway broken before he even opened it up. Those solder joints are all garbage and will definitely fail with time.
Thank you for the video. You should've played music on it first before disassembling it. You might break it yourself. Yet again, what do you expect from a $20.00 device?
These are also available from a couple of sellers on AliExpress; the amplifier seems to be a TI TPA3116D2.
Thanks for the video!
I don't know much about electronics and depend on guys like you to steer me in the right direction. I just bought one and hope it will solve the problem using my tablet in my shop.
Regards
Just bought one. Total junk. Only 1 LED lit up and the bluetooth didn't work.
You’re better off with a cheap Pyle or Lepai 😂
Sounded pretty good, I'm building a BT speaker for my inlaws for Xmas it will be run off a small car jumpstarter rechargeable unit, it hat BT, has USB input and charging output, I'm building in a Google home mini, all invaded in a WW2 ammo box. Led lighting around all the speakers via some 3mm perspects and tiny sound active lights. I need to have 12v output, 9v &7v so I picked up a couple of tuneable voltage boards. Small amp, I'm running a central 6inch 3way speaker and 2 sets of 2way and tweeter speakers. It has USB input plus 2 USB charge outputs, 3mm headphone jack input. So I've got my self drawn up wiring diagram and will see how it's all going to run....... I've built it about 100 times in my head, done dozens of sketches of the final product, I'm waiting on 1 more part then I think I'm up and ready to get it started........ Hoping all my calculations and ideas will work. It's to run outside by their pool and spa, so I'm trying to build it all 100% hands-free so the can"hey google" any changes, being music changes to volume control....... So fingers crossed......... At least the small jump starter battery supply will last a long time and takes over night to charge from zero to 100%. But when it's off and not in use, it will just look like an old WW2 ammo box....... I'm going for the, in wrap disappointed face to the open the box and wow face...... Just need my last 2 components to start wiring it all up to see if it will work be4 I go mounting and soldering everything...... Thanks for your upload, gave me more food for thought.....
I had a car audio Bose 1401 system derived from 901 drivers. They look EXACTLY like the same full range drivers. The 1401 was 100 watts total into 4 speakers. It was actually good stuff...for the 1980's.
Timely! Bought it. Yes, for the garage! Will test w/o disassembly. So... FYI, the datasheet for the TPA3116 Power Amplifier Chip has a linear power out with voltage. 16v goes 15/30w into 4/8 ohm, 24v goes to 35/70w into 4/8 ohm. Should be plenty loud.
Got it, everything tests out, all 3 inputs ok. Drives even big floor speakers. I used a lab power supply and basically, the voltage doesn't matter. Draws more amperage at lower voltage but same volume (class D! should have known that). 0.2 amp will get you quite a bit of sound.
Thanks Colin!
thank you so much for your close look at the bits, the IC's and the like!
If it hasn't got a micro chip, you're not interested. Bring back all discrete stereo amplifiers with massive power supplies. Those things always sounded better to my ear.
..and the classic tube amps.
Any video that features an IBM laptop gets an automatic thumbs up.
That chip is only the Bluetooth controller. It's made by Jie Li (electronics).
If you touch a circuit board without an antistatic wrist strap attached to a ground, then you can introduce 20,000 volts or more of static electricity. It only takes 7 volts to destroy some chips. Also work on an anti static mat. Always check the unit before you disassemble it, then you can narrow down the problem cause.
I vote "hidden Gem."
I bought one too. No issues with mine. I have it feed by a 20 volt laptop power supply that can put out 3.25 amps. I am using Paradigm Mini Monitor speakers and all in all I am very satisfied. I suppose I could get more power if I used a 24 volt supply with a higher amp rating but it has plenty of volume for the 15' by 20' room it is set up in, and it does not seem to have any heat issues after a month of being used daily.
What is the brand name of this amp?
@@maxlever Miniamp1. Towards the end of the video he tells you the best way to search EBay to find it. There are at least half a dozen sellers that sell it. I bought mine for roughly $18 from a state side distributor and had it within 4 days.
Excellent video. Im glad other people who doesnt just buy into the mono smart speakers.
For those who like to take apart things.... Always try the product first then tear it apart and play. That way you have something to reference back to. like did it work before I tore it apart.? Now you won't know. Great video though thank you.
It's doesn't have a butchered printed text "Miniamplifier" across the top, it's "Miniamp1"...with the number "one" at the end. Widely used rebrand OEMs like the OEM that made this mini-amp aren't too terrible since they have to meet some requirements set forth by retailers looking to sell their wares. If they missed the English portion of it, I would've expected the overall quality to be way worse. Speaking from a Chinese commerce and importer's point of view.
I wanted a little amp for the workshop.
Had already looked at the model shown before.
Your video animated me to buy now.
The functions and the quality that was justifiable for the price were the deciding factors. Thanks a lot!
It will replace a heavily modified and run-down WEGA ADC-2 (1978!).
I think he has NOT damaged it and the problem with the noise (only!) with bluetooth has nothing to do with opening the device (without testing it before). It can also be a design-problem because of missing (or not good enough) ground around the BT chip or antenna. If you have the same problem with noise via BT just touch the chip or its contacts with your finger, the noise often will stop.
I was searching "hours" for the reason of this noise on my amplifier and finally found it. I fixed it with a little bit of paper (as isolator), aluminium and a short cable to ground.
If you have still noise problems, replace the powersupply with a battery and verify.
Sorry for my (bad) english, I'm german.
Have you come across the CMoy amplifier in your investigation? It's an internet design made available for anyone. You can breadboard it, make your own PCB, buy a kit, or buy pre-made units from individuals. I bought one of them years ago which uses a rechargeable 9V and a DC jack, the sound quality is AWESOME. These days you can get ones which charge off USB. Strong recommend on CMoy amplifier if you can find one.
At 3:57 the LGR connector is attached to the board, after you remove it at 4:04 the connector is broke from the board. Then you complain about the short you created like it was the manufacturers fault after you put it back together. Using the proper tools to remove the connector instead of yanking on it might have prevented the damage.
18:20 you literally took it apart and then you start whining about the build quality you took it apart so what Bill quality did you put into it
i built one on a breadboard with a TCA0372 1A dual opamp which i recycle from an old table top cd player.
i think the fun part is when i realized i got the calculation right when i hook up to an oscilloscope and no magic smoke.
Do you have any scratch builds that equal high end units for amplifiers, speakers, or microphones?
Perhaps they tuned those cap lead lenghts to act as RF chokes for a specific harmonic frequency of the PWM amp in order to minimize ultrasonic distortion ? ;)
@ i didn’t say inductor. They are certainly antennas, and hence their propensity to attenuate (or, “choke”) any rf energy that is matched to the impedance of those lead lengths (hence my “ultrasonic” comment).
I had put a “;)” but I guess you missed it 😛
@ I actually said “act as…”Cognitive dissonance harder 😝
Aren’t you up on how RF antennas work? Hint: they radiate energy optimally at a specific frequency. Google “simple RF notch filter”.
What are the BOSE full range speakers like at over 10 khz? How to make an amazing full range speaker sound (with the extra khz). Make a pair of extremely thin sticks that are also very short sticks (only like 2 mm tall, made out of a split toothpick). Then glue each stick onto the dust caps of the FR drivers and stick a tiny piece of (coffee can seal) foil onto the ends of the sticks. Cut the foil pieces in a teardrop shape like 1/4" x 1/8" big. I suggest you prick a hole in the tiny foilies to make them easier to glue onto the ends of the sticks. It's REALLY TEDIOUS but really cheap and your full range speakers will STING like crazy in the top end.
It's acoustic separation technology, the foily is vibrating completely independently of the dust cap, and that is the big secret. If you attach the foily directly to the dust cap you get NO WHERE NEAR the effect. When it's on the end of the stick, acoustically it's like a miny 2-way coaxial driver, giving the top end a completely separate vibration to the main cone. And this extends the highs way better than just sticking the foilie directly to the dust cap.
Why bother spending time cutting down those caps pins if they don't touch anything? It's a reasonable choice they made on something this cheap.
If I remember correctly APPJ makes a small 3w tube amp.
Just got a DTA-2.1BT2 from parts express. It’s surprisingly good for a mini 2.1 amplifier.
Remember Class-D amplifiers are very efficient (90% or more) and at normal non-party conditions it doesn't produce any (extra) heat. You mention it is the Texas Instruments TPA3116 , it starts to produce 'heat' (a little warm) when you feed it above 12 volts. You can also power the TPA3116 with only 5 volts (if there is no voltage requlator inside this that requires a higher voltage), I have a few boards that works nicely on 5 volt (USB power) and if you use decent speakers (hook up 100W kenwood, 96db 1W, Wattage don't say everything - sensitivity and construction matters) , it is very suitable to use at computer, garage, etc to use at normal (and pretty loud) listening conditions.
1W, 3W or 5W can be very loud when using a pair of decent speakers, especially using Class-D amplifiers. The TPA3116 is really a good and efficient chip because of the wide input range and decent crisp quality of sound, even on a low(er) voltage. I like to see if it is possible to run it at usb power, I think it is possible besides the required input specs.
You didn't try the USB input connected to a computer, I think (by experience of JL 'branded' chips) that there are some hidden features.
The heat-sinked IC on the back board is likely a class D amplifier (switch-mode outputs). This is re-enforced by the inductors present on the each of the speaker terminals.I don't think overheating will be a problem.
Class D isn't magic. Yes, its a lot more efficient (90-95%) than typical class AB (65%), but it still has to dissipate some heat and that is very tiny heatsink in an enclosed space with no path to outside.
@@goatofpower True, there is no magic. However, the heat produced depends on how hard you drive MOSFET gates, and how fast the MOSFETS switch between off and on states. That switching time is where most of the heat is being produced. Minimize the switching time, and you minimize the heat produced.
We'll never know if your disassembly caused the problem or not. I really wish you and other reviewers would test first and THEN disassemble.
Is it possible it's name is Mini Ample?
In all fairness, it should be able to withstand a disassembly without falling apart 😒
Loved the EEVblog reference! Great video
Increase the voltage by 1 or 2 watt. Depends on the ohms your dealing with. Built a heat sink to prevent heating up..
Thanks Colin. I need one also for my garage. Great review as ever.
I've got one of those for about a month now, brilliant in nearly every way, except one thing that makes me mad each time : the voice volume (and the litte audio jingle at startup) is insanely high and i can not find how to modify it. Yours doesn't seem to have this voice over and jingles, it's kinda weird.
Maybe he killed it on disassembly 😂
Hmmm. This is one of those devices that I don’t need, but now I’m thinking Where COULD I use it?
it would be cool if you "upgraded" the amp. replacing all the caps with quality caps, using power tools to make some vent holes, etc.
Great review! I think the writing on the unit may have been a European “1” (number one), instead of an “l” (lower case L), to read “miniamp one”
you broke the solder joints on the RGL connector when you removed the cables . It is clearly visible at 7:41.
I see that he pulled the plastic housing off.. and probably didn't push the connector all the way back in when he re-assembled it... another reason why you need to disassembly it... AFTER testing it!
Hand drill a grid of small holes through the top bottom near the chip. Add a bigger piece of metal on top of the other. The googlnet can tell you what adhesive is decent for cheep.
Have fun with it. Make a slightly larger enclosure that has the above features and say it's a custom built amp just for garages. Bend an old gas can or put it in a cigar box. My brother-in-law user to do stuff like that in our shop. We'd take the speaker-loaded front panels and staple them into large cardboard boxes of "correct" volumetric size and A-maze our friends. Fun is fun!
My brother made a killing back in the 70's building custom speaker boxes using particle board and speaker cloth. We would salvage speakers out of old stereo units and he would sell eather custom built preinstalled or you could choose from a list of Radio shack speakers. He sold a ton of those before getting bored with it. I believe it financed his first car. 1970 Duster. Those were the days. I am restoring old lawn mowers to finance a Conversion van right now.
I did it!! I purchased one for my outdoor theatre , $25 tax and shipping inc. thanks
Darn it, I'm too late, $39,99 and up. This is why I usually don't bother watching video's like these. I'll just stick to my $2 Pam8403.
OK .... so I am old and remember the massively heavy amps that were common in the late 70s. Good thing with them is after several decades of working flawlessly, they atleast made a great doorstop or weight for holding down wood projects as the glue dries 😁 Much agreed on Test them Dismantling idea. Wish those with Amp Dynos would start testing more of these budget D class amps to see if they meet claimed outputs. Worst case you have a light duty use Paperweight if all else fails
My 1976 kenwood is still running as a dedicated guitar amp (added a cooling fan),wonder how that little unit will fare in the long run...😒
Many of those old amps are or were fixable, since they just used standard transistors. Another plus.
Actually, I think the metallic contacts act as the heat dissipaters, they are big enough and get rather hot while the amplifier works - though they do not touch the chip directly.
The sound level bar is absolutely useless: I just put a sticker on the green/yellow region and can only see two red indicators. :-)
P.S. Just discovered that it is possible to hook up Sumsung s7 to this device via a MiniUSB adapter and use it as an audio amplifier for the phone. The S7 has recognized the device immediately.
UPDATE. A couple of days of good work and now the sound in one of the channels disappears in about 20 minutes after being switched on a insignificant load. It looks like the heat affects the soldering somewhere inside.
Why did you not test run it first before taking it apart?
Can you tell us if the amp POPS in the speakers when you apply power to it? Also is the amp stays On when you power cycle it?
if you use laptop charger in audio devices , it could make some distortion.
ground loop. laptop charger is probably earth referenced as every PC running on AC.
@@Mr.Leeroy Mmm, no, most laptop chargers, at least in the US, only use hot and neutral. The reason it might introduce distortion is because PSRR is typically only good in amp chips when the noise isn't high frequency. However, some people, particularly those who like trance misc, like the more lively treble distortion that results. Purists would never settle for it though, want it to sound the way it's supposed to without that coloration.
What’s the purpose of this projects?
You Tube inform consumers?
Frank‘s School inform? We missed something.
That's a gem and a half if I've ever seen one
I build amps. Would you consider reviewing one of my amps if I designed it and built it for you to your likings?
Is disassembling before use okay?
@@pirate0jimmy sure!! :)
he would destroy your reputation before he even knew if your product works. what a horrible idea. this video makes me want to start a channel and do it the right way and even test the same stuff he broke just to prove his channel should be delete
@@djfirestormx thanks. You are right. Tho if you start a channel I'd be happy to give you stuff I make for review :)
So far I've been designing amps. Now I'm working on consumer affordable room correction system. One of my customers is begging me to design a pair of speakers for him so I'll also give that a try.. I might start a company soon :)
Your craftsmanship and quality would speak for itself. This dude is pretty honest and knowledgeable. Would you rather have some hot head like DJ storm reviewing your product? He’d probably call for your execution if he didn’t like it. Use some common sense here
Nálam az iLike bluetooth hangszóró adott ki ilyen hangot, mikor is a bluetooth vevőegység bezavarta a végfok IC hangkimentét. A megoldás nálam az volt hogy egy kis méretű csavaralátétet ragasztottam a tekercs tetejére, és a zaj megszünt.
I got the LvPin 2.1 hooked up to two
NIB SET OEM 6x8 Genuine Ford Speaker XC2F-18814-BA with GRILLS 25 WATT 4OHM and one 8" subwoofer all installed into a plastic cooler and I just plug it into my cig lighter it blasts me out of car!
Dude! Really liking your great wave of kanagawa wallpaper!
Just bought one of these to use on my workbench, been after something like this for a while so thanks!!!
Personally, I'm not sure if I'd buy something like that given that I have a USB DAC on my mixer console. For what it is though I could see people actually wanting this. You should have a look around Ali Express's website and Amazon too. Often the sellers of such devices have a store on those sites too. In fact, sometimes that's where people get them to sell on eBay. Great video... Liked & Subbed